When Richard Amero wasn't at his SDG&E post as materials management technical analyst, he was in the library researching San Diego history.

He laboriously scrolled microfilm reels of local newspapers, tracked down original documents and manuscripts and diligently wrote out the headlines and whole passages on topics as wide as opera stars, the Mexican-American War and Christmas in early America.

But his obsession was Balboa Park -- how it was created, who developed it and how its landscape, architecture and overall plan came together.

The result was 226 binders of clippings, copies of magazine articles and a day-by-day summary of the park's development -- all referenced in articles prepared for historical journals and reflected in numerous letters and commentaries to local newspapers.

"I like the grand, open-air, natural quality of a city park," he said in a letter in 1999. A city park, he added, should offer visitors a place "without paying money for something from a tube, bottle or television and movie screen."

Amero died of prostate cancer at 88 on Dec. 22 at Fredericka Manor retirement community in Chula Vista.

"Every city should have a Richard Amero," said University of San Diego historian Iris Engstrand, who edited several of his articles for the Journal of San Diego History.

He was more compiler than historian, she said, because he gathered the facts and background of many topics but offered little critical interpretation of what he found.

"He was a consummate collector of information and putting it down and making sure people when doing research would refer to it," she said.

But occasionally, Amero would enter the public discourse and express his opinion. Most recently, he came in favor of the plan to remove cars and parking from the center of the park and build a bypass bridge, proposed by Qualcomm co-founder Irwin Jacobs. Engstrand read Amero's statement on that view to the City Council last summer.

Richard Crawford, former archivist at the San Diego History Center, said Amero's notes are indispensable to anyone researching the park and many other topics.

"Most people would have notes that are unusable to anybody else," he said. "It's as though he wanted it for posterity -- he wanted to leave it for others. Researchers just don't do that and if they do, it's too late."

The Committee of 100, the group that promotes the preservation of Balboa Park's architecture and landscaping, gave Amero its Gertrude Gilbert Award in 2010 for his life's work. Gilbert headed the music program for the park's two expositions and led the drive to save the expo buildings from demolition.

"I sat with him just a few weeks before he died," said Committee President Mike Kelly. "He wanted to do some more traveling and some more writing. He was in no condition to do either one of them."

One of Amero's closest friends, Nick Miller, accompanied him on many research expeditions and likened him to a walking encyclopedia.

"He was always motivated by learning, his whole life -- learning and education," Miller said. In retirement, Amero became adept at writing and researching on a computer and became "unbearable" until Miller could come by and fix a glitch.